The present invention relates generally to fluid filters. The present invention relates more particularly to an air filter system for mitigating the exposure of an airline passenger to undesirable airborne particulate and/or chemical substances.
Modern passenger aircraft, such as commercial jet airliners, commonly include a passenger support unit (PSU) located generally above each passenger""s seat. The PSU typically includes a reading light, an air supply nozzle and an emergency oxygen mask for each passenger. The air supply nozzle facilitates control of the quantity and direction of air provided to the passenger.
Such contemporary air supply nozzles are typically adjusted by the passenger, so as to direct a stream of air upon the passenger""s face and/or torso. This stream of air is refreshing and is intended to enhance the comfort of the passenger.
Although such contemporary air supply nozzles do typically enhance the comfort of a passenger during flight, such contemporary air supply nozzles suffer from inherent deficiencies which tend to detract from their overall utility. For example, the air flowing through an air supply nozzle and being directed toward the face of a passenger may contain undesirable airborne contaminants such as germs, dust and pollen.
The air circulation system of a commercial airliner typically has a particulate filter incorporated therein. However, such filters must be changed periodically in order to maintain their effectiveness. Although both the Federal Aviation Administration (FAA) and the aircraft manufacturer provide guidelines regarding the frequency with which aircraft air recirculation filters must be changed, there is no assurance that the airlines actually follow such guidelines.
Indeed, there is generally a substantial incentive for airline companies to disregard such guidelines, since more frequent filter replacement is costly, not only in terms of parts and labor but also in terms of the down time of the aircraft incurring such maintenance (during which the aircraft is clearly not contributing to the revenue of the airline).
There are documented cases of germs being transmitted among passengers during an airline flight. For example, in one incident reported by the Centers for Disease Control and Prevention, six of 257 passengers contracted tuberculosis, presumably from a single inflected passenger aboard the airliner.
As a further example, an airliner containing one person who had the flu was known to sit on the ground for approximately three hours. Three days later, 38 of the 54 people aboard the aircraft had contracted the flu.
Anecdotal evidence of this sort is abundant. Moreover, it is not difficult to understand that when a number of people are crowded together into a comparatively small space, such as that afforded by a commercial airliner, airborne contagiums will tend to be transmitted from one passenger to another.
In view of the foregoing, it is desirable to provide an air filter system which mitigates the exposure of a passenger to undesirable airborne contaminants. More particularly, it is desirable to provide such an air filter system which is configured so that a passenger may install and utilize the air filter system personally, so as to assure the adequacy of the filtration afforded thereby.
The present invention specifically addresses and alleviates the above mentioned deficiencies associated with the prior art. More particularly, the present invention comprises an air filter system having a housing and a filter medium. The housing is configured to clamp to an air supply nozzle, such as that of a commercial airliner.
As discussed in detail below, the air supply gasper nozzles of different airliners vary considerably in their configuration or geometry. In order to enhance the utility of the present invention, the air filter system is configured so as to clamp onto a wide range of nozzle geometries utilizing a single embodiment thereof.
As used herein, the term clamp is defined to include attachment by urging together at least two generally opposed members of a first device (such as the air filter system of the present invention) so as to capture and grasp a second device (such as an air supply nozzle). Thus, according to the present invention, the term clamping includes grasping by a plurality of generally opposed fingers, as discussed in detail below. Those skilled in the art will appreciate that various other structures are likewise suitable for effecting such clamping. For example, clamping may alternatively be accomplished via a common hose clamp-like device or via any other similar structure. Moreover, clamping is defined herein so as to apply to any type of device which applies a compressive force to another device, so as to attach the two devices to one another.
The housing may be configured to clamp to any desired type of air supply nozzle, as discussed in detail below. According to one aspect of the present invention, the housing is configured to clamp to the air supply nozzle of a commercial airliner, so as to provide air to a passenger of the airliner in a manner which mitigates the exposure of the passenger to undesirable airborne contaminants. Further, since the housing is configured to be clamped to the air supply nozzle by the passenger, the passenger is assured of the adequacy of the filtration afforded thereby. That is, the passenger is able to assure proper operation of the air filter system by performing the necessary filter medium changes, as needed.
The housing is configured to direct air from the air supply nozzle through the filter medium, so as to remove undesirable airborne contaminants. In this manner, the undesirable transmission of contagiums and substances associated with allergies may be mitigated. Further, a substantial portion of other undesirable airborne contaminants may be removed. Indeed, carbon, ion-exchange resin, or another desired chemical filter medium may be included so as to mitigate the presence of undesirable chemical substances such as fuel, oil, or hydraulic fluid fumes. Thus, according to the present invention, cleaner, more pure air is provided to a passenger so as to enhance the passenger""s comfort during flight and also so as to mitigate health risks which might otherwise be present during the flight.
The filtered air stream from the air filter system can be utilized to force unwanted airborne contaminants away from the passenger""s breathing space. Thus, germs from the surrounding passengers, cabin dust and mold from inside the cabin can all be forced away from the passenger by utilizing the filtered air stream.
Preferably, the air filter system of the present invention comprises a collet which is configured to clamp to the air supply nozzle of an airliner. However, those skilled in the art will appreciate that various other means for clamping the housing to the air supply nozzle are likewise suitable.
As used herein, the term collet is defined to include any generally encircling or collar-like band, ferrule, flange or other device which comprises a plurality of fingers or finger-like projections which are capable of moving inwardly, so as to grasp an air supply nozzle.
According to the preferred embodiment of the present invention, the collet comprises a plurality of elongated independently articulated fingers which are movable inwardly so as to grasp the air supply nozzle of a commercial airliner. The collet is preferably configured such that the fingers are movable inwardly so as to grasp a gasper nozzle of a commercial airliner. However, as those skilled in the art will appreciate, the collet may be configured such that the fingers thereof move inwardly so as to grasp any desired type of air supply nozzle.
A clamp sleeve preferably receives a portion of the housing and the clamp sleeve urges the plurality of fingers to move inwardly, so as to grasp the air supply nozzle, when the clamp sleeve is moved, e.g., when the clamp sleeve is rotated with respect to the housing. The clamp sleeve and the housing are preferably threadedly attached to one another and configured such that the plurality of fingers move inwardly when the clamp sleeve is rotated clockwise from the passenger""s point of view. Thus, a passenger tightens the air filter system to the gasper nozzle by turning the clamp sleeve in the same direction, i.e., clockwise, that is used to screw a lightbulb into a socket. Thus, the threads which attach the clamp sleeve to the housing preferably comprise left-handed threads. Alternatively, right-handed threads may be used.
An opening is preferably formed in the clamp sleeve and the opening is configured so as to urge the fingers inwardly toward the air supply nozzle such that a distal portion of the fingers effect engagement with the air supply nozzle, so as to removably attach the housing to the air supply nozzle.
Preferably, a resilient clamp pad is formed to each finger, so as to enhance grasping of the air supply nozzle by the fingers. Each resilient clamp pad is preferably formed of molded polymer or elastomeric material such as silicone or urethane. However, those skilled in the art will appreciate that various other materials are likewise suitable for forming the resilient clamp pad. For example, the resilient clamp pad may alternatively be formed from cork, felt, or leather, as well as various different fabric and fiber materials.
The housing preferably comprises an air inlet port and an air outlet port. The filter medium is mounted within the housing such that air entering the housing via the air inlet port is filtered by the filter medium prior to the air exiting the housing via the air outlet port. Alternatively, the filter medium may be attached to the outside of the housing, such that the filter medium covers the air outlet port thereof, for example.
The housing preferably comprises a separable two part housing defining first and second housing sections thereof. The first and second housing sections of the two-part housing preferably attach to one another via a plurality of bayonet detents to facilitate quick and convenient separation and attachment thereof. As used herein, the term bayonet detent is defined to include a detent which locks two items to one another when one of the items is pushed toward the other item and then rotated with respect to the other item, such as the type of detent commonly used to attach a bayonet to a rifle barrel.
Alternatively, various other means of attaching the first and second housing sections together may be utilized. For example, the first and second housing sections may be threadedly attached to one another. As a further alternative, fasteners, such as nuts, bolts, screws, etc., may be utilized to attach the first and second housing sections to one another. Indeed, any method which facilitates the convenient changing of a filter medium disposed within the housing may be utilized to attach the first and second housing sections to one another.
Separation of the first and second sections of the two-part housing facilitates removal and replacement of the filter medium.
The filter medium is preferably disposed within the housing such that the filter medium is held in place by the first and second sections thereof.
The filter medium preferably comprises a disposable filter medium, such that the disposable filter medium may be removed and replaced with respect to the housing when or before the effectiveness of the disposable filter medium is reduced substantially due to use. The filter medium preferably comprises an electrostatically charged, polypropylene, non-woven membrane.
Alternatively, the housing may be sealed, i.e., not easily opened, and the air filter system may be considered disposable. That is, rather than change the filter medium when the filter medium is no longer adequate for removing airborne contaminants from the air passing therethrough, a new air filter system is used. The new air filter system may utilize the clamping mechanism of the old air filter system or, alternatively, may include a dedicated, disposable clamp mechanism of its own.
A seal, preferably formed of a resilient polymer foam material, is optionally disposed proximate an air inlet port of the housing and is configured to mitigate air leakage intermediate the housing and the air supply nozzle when the housing is clamped to the air supply nozzle. That is, the seal is positioned upon the housing and is configured such that attachment of the housing to the air supply nozzle effects at least some compression of the seal, such that air leakage between the seal and the air supply nozzle is mitigated. Preferably, the seal is attached, e.g., via adhesive bonding, to the housing.
Preferably, an air outlet nozzle is pivotally attached to the housing so as to facilitate aiming of air exiting the housing. The air outlet nozzle of the housing mimics, to some degree, the aimable air outlet nozzle of the airliner. This may be desirable since, in some instances, the air filter system 10 of the present invention may inhibit aiming of the gasper nozzle 30. Thus, even when the air filter system of the present invention is installed upon an air outlet nozzle of an airliner, the passenger may direct the air output therefrom as desired.
Pivotal attachment of the air outlet nozzle to the housing is preferably facilitated by forming a ball upon the housing, preferably surrounding the air exit port thereof. The air outlet nozzle defines a complementary socket which receives the ball, so as to facilitate aiming of air exiting the housing. Alternatively, the ball may be formed upon the air outlet nozzle and the socket then formed upon the housing. Those skilled in the art will appreciate the various other means for facilitating aiming of air exiting the housing are likewise suitable.
A mounting assembly facilitates mounting of the housing to the air supply nozzle. The mounting assembly comprises the seal, the plurality of fingers defined by the collet, and the clamp sleeve.
Although use of the present invention is described and illustrated herein as being intended for the filtering of air from an airliner""s air supply nozzle, those skilled in the art will appreciate that various other applications of the present invention are likewise suitable. For example, the air filter system of the present invention may similarly be utilized to filter air within the passenger compartment of various different types of vehicles, such as trains, buses, cars, trucks, boats, private aircraft and helicopters. Indeed, the present invention may be utilized to filter air in a wide variety of applications. Thus, discussion and illustration of the present invention as being specifically applicable to the filtering of air within an airliner is by way of example only and not by way of limitation.
The air filter system of the present invention may be formed substantially from a low cost, injection molded polymer material. Therefore, the air filter system of the present invention is inexpensive to manufacture and provides a low cost option for those airline passengers who are concerned about the presence of airborne contaminants aboard commercial airliners and the like. Since the air filter system of the present invention is simply clamped onto the existing gasper nozzle of a commercial airliner, such as via the aforementioned attachment mechanism, the air filter system of the present invention is convenient and easy to use.
According to an alternative configuration of the present invention, the housing is attached to a gasper nozzle via an adhesive, which is preferably formed upon a foam seal or gasket. According to this alternative configuration of the present invention, a passenger preferably merely removes a protective paper layer from the air inlet side of the housing, so as to expose an adhesive layer. The air filter system is then attached to the gasper nozzle by merely pushing the housing against the gasper nozzle, so as to effect adhesive bonding of the housing to the gasper nozzle.
Preferably, the adhesive and seal are formed such that the air filter system may be removed from the gasper nozzle without leaving a noticeable amount of adhesive thereon. Further, the adhesive and seal are preferably configured such that pulling a tab or the like of the seal effects removal of the air filter system from the gasper nozzle while also destroying the seal. Thus, the seal may be considered a one use only item. Additional seals may then be provided separately from the air filter system to facilitate reuse of the air filter system. 3M COMMAND ADHESIVE(trademark) (a federally registered trademark of Minnesota Mining and Manufacturing Corporation of St. Paul, Minnesota) is one example of such an adhesive coated seal.
Thus, the present invention provides an inexpensive and easy to use air filter system for mitigating exposure to undesirable airborne contaminants such as germs, dust and pollen which may be disseminated via a passenger""s air supply nozzle on a commercial airliner or the like.